As handheld electronic devices such as touch phone and personal digital assistant (PDA) phone have gained great popularity and rapid advance, manufacturers are dedicated to the attempt of integrating various functions in the same handheld electronic device to meet consumers' versatile needs.
For example, when the user makes a phone call with a PDA (personal digital assistant) phone, the user may need to take down the content of the talk during the call such as a telephone number or an address provided by the other party. By integrating a notepad application into the PDA phone, the user is able to take down the content of the talk during the call. Besides, PDA phone normally has a stylus with which the user can easily operate the PDA phone. If the use needs to activate the notepad application while making a phone call with a current PDA phone, the user has access many paths and menus to select and activate the notepad application, and thus which is inconvenient for the user and causes the other party to wait over a long time.